I spent a lot of time on buildozer and this error also. In my case Python-for-Android made wrong path to clang (that CC executable).
Here we have
'/home/pi/.buildozer/android/platform/android-ndk-r19b/toolchains/llvm/prebuilt/linux-armv7l/bin
So check if the folder's name in '/home/pi/.buildozer/android/platform/android-ndk-r19b/toolchains/llvm/prebuilt/ is really 'linux-armv7l'. If it's not just go to your python-for-android folder and there /pythonforandroid/util.py
Open it and find there 'build_platform' variable and after that you can just comment code that is going after '=' sign, and write there your real folder's name as a string. For example:
build_platform = 'linux-x86_64'
It helped me, maybe it will help you.
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